Hauck et al. in U.S. Pat. Nos. 3,898,236 and 3,965,102 disclose the preparation of 4-[(substituted phenyl)ethenyl]-N-alkyl or phenyl-lower alkyl substituted 1,2,3,6-tetrahydropyridines. Hauck et al. employ such compounds as intermediates in the preparation of various 2,3,3a,4,6,7,8,9,9a,9b-decahdro-4-(substituted phenyl)-1H-pyrrolo[3,4-h]isoquinolines.
Gautier (Ph.D Thesis, University of New Hampshire, 1966) discloses the preparation of 4-[(phenyl)ethenyl]-N-methyl substituted 1,2,3,6-tetrahydropyridine.
Peskar et al. in the Journal of Pharmacy and Pharmacology, Vol. 28, p. 146-148 (1976) disclose the inhibition of 15-.alpha.-hydroxyprostaglandin dehydrogenase by the anti-ulcer agent carbenoxolone.
Rajadhyaksha et al. in U.S. Pat. Nos. 4,016,223 and 4,038,415 discloses various compounds which inhibit prostaglandin dehydrogenase and lower blood pressure and potentiate the cardiovascular effects of exogenous prostaglandins.